Re: [GSoC][PATCH] submodule: port submodule subcommand 'add' from shell to C
- From
Junio C Hamano <gitster@pobox.com>
- Date
- Aug 24, 2020, 20:46 UTC
- Message-ID
- <xmqq1rjv4vrb.fsf@gitster.c.googlers.com>
- In-Reply-To
- <43337924c09119d43c74fdad3f00d4dab76edb51.camel@gmail.com>
Kaartic Sivaraam <kaartic.sivaraam@gmail.com> writes:
Show 25 quoted lines
>> > else >> > git ls-files -s "$sm_path" | sane_grep -v "^160000" > /dev/null 2>&1 && >> > die "$(eval_gettext "'\$sm_path' already exists in the index and is not a submodule")" >> > fi >> >> Hmph. So, >> >> - if we are not being 'force'd, we see if there is anything in the >> index for the path and error out, whether it is a gitlink or not. >> > > Right. > >> - if there is 'force' option, we see what the given path is in the >> index, and if it is already a gitlink, then die. That sort of >> makes sense, as long as the remainder of the code deals with the >> path that is not a submodule in a sensible way. >> > > With `force, I think it's the opposite of what you describe. That is: > > - if there is 'force' option, we see what the given path is in the > index, and if it is **not** already a gitlink, then die. > > Note the `-v` passed to sane_grep.
Thanks.
Yeah, "-v ^160000" passes (i.e. detects an error) if the path exists and it is anything but gitlink, so missing path is OK (no input to grep, and grep won't see a gitlink), a blob is not OK (grep sees something that is not a gitlink), and a gitlink is not OK.
If $sm_path is a directory with tracked contents, ls-files would give multiple entries, and some of which may or may not be a gitlink, but most of them would not be, so it is likely that grep would find one entry that is not gitlink and error out. Which is a good thing to do.
Show 14 quoted lines
>> > } else {
>> > int err;
>> > if (index_name_pos(&the_index, path, strlen(path)) >= 0 &&
>> > !is_submodule_populated_gently(path, &err))
>> > die(_("'%s' already exists in the index and is not a "
>> > "submodule"), path);
>>
>> Likewise. The above does much more than the original.
>>
>> The original was checking if the found cache entry has 160000 mode
>> bit, so the second test would not be is_submodule_populated_gently()
>> but more like !S_ISGITLINK(ce->ce_mode)
>
> Yeah, the C version does need a more proper check in both cases.Especially, the case where $sm_path is a directory with tracked contents in it would need a careful examination.
Thanks.